Like the Moon, does the Sun play any role in causing ocean tides?

Tides are the movement of the ocean waters in response to the gravitational pulls of the Earth, Moon and Sun. Although the Sun is 27 million times more massive, the Moon’s tidal influence is greater because it is much nearer to the Earth. The Sun’s tidal force is only about half as strong as that of the Moon. The Moon rises approximately 50 minutes later each day, and so, too, the time at which the tide comes advances by 50 minutes every day. As the Earth itself rotates every 24 hours, any point comes directly opposite the Moon and moves away from it once every 24 hours 50 minutes. The Moon’s high tide producing forces act both, when the Earth is facing toward and away from the Moon, so the interval between high tides is generally 12 hours 25 minutes.

The story of the tides is complicated by the fact that the influence of the Sun and Moon varies with the distances of the Moon and Sun from different parts of the Earth. When the positions of the Sun and Moon are at right angles to each other in relation to the Earth, as at half Moon, their tide rising effects act in opposition and neap tides occur (the lowest high tides and the highest low tides). But when the Sun and Moon are diametrically opposed to one another at full Moon, or when they are both on the same side of the Earth at New Moon, their tide generating effects are complementary and spring tides occur (the highest high tides and the lowest low tides). Spring tides have a range (the difference in level between successive high and low waters) thee times greater than that of neap tides.

Additional reading:
Earth tide (Wikipedia)

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